What is the use of wchar_t in general programming?

Question

Today I was learning some C++ basics and came to know about wchar_t. I was not able to figure out, why do we actually need this datatype, and how do I use it?

Answer 1

wchar_t is specified in the C++ language in [basic.fundamental]/p5 as:

Type wchar_t is a distinct type whose values can represent distinct codes for all members of the largest extended character set specified among the supported locales ([locale]).

In other words, wchar_t is a data type which makes it possible to work with text containing characters from any language without worrying about character encoding.

On platforms that support Unicode above the basic multilingual plane, wchar_t is usually 4 bytes (Linux, BSD, macOS).

Only on Windows wchar_t is 2 bytes and encoded with UTF-16LE, due to historical reasons (Windows initially supported UCS2 only).

In practice, the "1 wchar_t = 1 character" concept becomes even more complicated, due to Unicode supporting combining characters and graphemes (characters represented by sequences of code points).